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Types of Reactions

  1. Jan 30, 2006 #1
    I thought I knew what I was doing but then I checked over some examples and now I'm not so sure...

    Finish the following reactions and balance the equations.

    NaOH(aq) + Fe(NO3)3(aq) -->

    NH3 --> N + 3H

    H2 + O2 --> 2HO

    Mg + H2SO4 -->

    That's all I did before stopping because I didn't want to waste my time doing them if I was messing it up.
  2. jcsd
  3. Jan 30, 2006 #2


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    I'd recommend learning the four basic types of reactions:

    These are just simple, generic examples to understand the process.
    Synthesis: A + B --> AB
    Decomposition: AB --> A + B
    Single Replacement: A +BC --> AC + B
    Double Replacement: AB + CD --> AD + CB

    Do you have any experience with these?
  4. Jan 31, 2006 #3
    Both Nitrogen and Hydrogen exist as diatomic molecules. Take a look at the oxidation numbers of the elements and refer to common ions and compounds. Knowing this, you should be able to complete the reactions and balance them on your own.
  5. Feb 2, 2006 #4
    t!m-- Yes, I know a little about those, I just took notes on them. ^_^

    The first one is a little long...what would I have to do with that one? o_O

    Second -- Decomposition?
    Third -- Synthesis?
    Fourth -- Single Replacement?

    Was what I had down wrong? This is what threw me, "The products must conform to the rules you learned in assignments 3.05 and 3.06. In other words, the new products you write down must be neutral, that is the positive and negative charges must cancel out. For instance, if Lithium oxide is a new product, Lithium has a charge of +1, Oxygen a charge of –2. So the new compound formed would be: Li2O" I had trouble with this last year and since learning it on my own wasn't working, I got a tutor. However, my tutor began to touch on this but then I had to leave and that was the last session I had so I was left sort of hanging there.:rofl: I'll have to try and find something about this in the text book I was loaned...

    NaOH(aq) + Fe(NO3)3(aq) --> FeOH + NaN3O9

    NH3 --> 3H + N

    H2 + O2 --> 2HO

    Mg + H2SO4 --> H2 + MgSO4

    What about that?
    Last edited: Feb 2, 2006
  6. Feb 6, 2006 #5
    Could someone please tell me if I got those right? I'm still hanging here...:wink:
  7. Feb 6, 2006 #6
    Wrong. Oxidation state of OH is -1. Fe does not have a +1 charge.

    Wrong. Both of these (H,N) are diatomic.

    Wrong. Think of the most common substance containing H and O and its empirical formula.

    Correct, but I am not too sure that you fully understand how you came to this conclusion based upon the previous answers. Go back through your book and read up on the common ions.
  8. Feb 6, 2006 #7
    I definitely don't understand what I'm doing then...I'll see if I can find anything in my book or on the lesson page. But, while I do, could someone possibly link me to a site that'd help? ^_^
  9. Feb 6, 2006 #8
    Alright, let me see if I got this...to do this, I have to look at the electrons and protons involved, right?

    H2 + O2

    Hydrogen has one electron and one proton. In order for it to have a noble gas configuration, it would be easier for it to lose it's one electron than it would be to gain seven more...so, after it loses it, it would be positive (+1). Oxygen has eight electrons and eight protons...it has six valence electrons. It would be easier for it to gain two electrons than it would be to lose six so it would become negative (-2).

    Ah, from there I'm lost though...now what?:confused:
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